Fastening for fountain pen caps



March 5, 1940. w, 5 LA Y 511 2,192,644

FASTENINQ FOR FOUNTAIN PEN CAPS Filed Feb. 21, 1938 2, m e M n mv 9 m Xmw a m %m h M lllllllll. W W 5 e G I mix Patented Mar. 5, 1940 i pUNITED STATES PATENT OFFICE FASTENING FOR FOUNTAIN PEN CAPS Wallace E.La May and George W. Chance, Minneapolis, Minn..

Application February 21, 1938, Serial No. 191,663

5 Claims. (Cl. 12042) Our invention relates to fountain pens and is 1showing a part on the same enlarged scale as directed to improved meansfor coupling the 010- in Fig. 6. 7 sure cap to the barrel of the pen.The barrel of the fountain pen is indicated by Generally stated, theinvention consists of the the numeral l and the pen point appliedtherenovel devices, combinations of devices,,and arto in the customaryway is indicated by the 8 rangement of parts hereinafter described and.denumeral II. This barrel and pen point may be fined in the claims.considered of the standard construction, except Hitherto it has been thecommon practice to that the barrel ill, at its pen-carrying end, isconnect the caps to the barrels of fountain pens provided w thoutstanding lock lugs or projec- W by screw-threaded engagement; and incertain' tions l2 the 1 may either be formed integral with of such pensthere has been provided an axially the barrel 0 may be of metal or othermaterial movable yieldingly pressed inner cap or sleeve rigidly appliedto the barrel. For a reason herewhich, when the threaded outer cap isapplied inafter noted, the barrel Ill, at its butt end is to the barrel,will enclose the pen point and be shown as provided with a disc-likepressure plate yieldingly pressed against the, end of the barrel. l3swivelled thereto by a counter-sunk screw I4 r These older forms ofcaps, with the threaded or the like. engagement, are slow of applicationand slow The outer end of closure cap l5 here illustratof removal andwill frequently become unscrewed ed and preferably employed is providedwith an and removed, exposing the pen point to the vest inner cap orsleeve l6 that has limited axial or coat to which the pen is applied,with the removement therein and is yieldingly, pressed by 20 sult thatink will be dabbed on said garments a coiled spring l1 or otherresilient member and sometimes the cap will be lost. which, in thisinstance, reacts against a plug .l8 Our invention is directedparticularly to an imscrewed into the orter or closed end of .the capproved form and application of bayonet joints, IS. The numeral l9indicates a spring finger whereby the cap can be applied to the pen bysuch as usually employed in connection with the 25 direct axial pressureand can be detached from caps of fountain pens and which, as hereillusthe pen barrel by simply slight rotary movement. trated, is clampedto the cap l5 by the flanged Our improvement above indicated can be andouter head of the plug l8. preferably is incorporated with the closurecap The important features of the invention are 80 having the aboveindicated yieldingly pressed axinvolved in a novel form of bayonet jointfor ially movable inner cap. In this last indicated connecting the capl5 to the barrel. The numcombination some highly important results areher of these bayonet joints may be varied but in obtained, all as willhereinafter more fully apthe drawing we htave illustrated the use of twopear in connection with the drawing which illusc yfl join 8. v trates apreferred form of the pen. For each lock lug I! on the barrel the cap I535 In the said drawing, wherein like characters 0 interior 0f itsenlarged bore 20 5 ed indicate like parts throughout the several views,w h aco-operating ay ve that con- Fig. 1 shows the pen partly in plan iand sists of a flaring lower portion 20a, a neck 20b, partly in axialsection; and a depressed or return lock pocket 200. It Fig. 2 shows theclosure cap removed from the is important to note see Particularly Figs-3 40 barrel, the same being chiefly in section on the d that the flaringportion of each same line as Fig. l, but with some parts in full; thetwo bayonet grooves extends through Fig 3 is an axial seamen the partsshown so that the walls of the grooves are brought to-. in detail in Fig2 looking at the same at n ht gether in sharp points or edges 20d.Regardless 1 t th g, n i d i F1 g of whether there are two or more ofthe lock lugs 9 1d 8:52 b d l2 and two or more of the bayonet grooves,the 1 :1 s S e e e n 0 8 an pen expanded portions of the grooves will bebrought P0 n together to form edges or points. This is impor- 5 isprspfictive on an enlarge? scale tant for in the structure illustratedwhen the i f g g gg iz s ggg g a portion of the cap forced ieridwiseonilao the barrel from any 5 posi on of ro a ion, the ock lugs l2 willbe di- Fla, 6 is a enlarged View P y in De D rected first upward throughthe channels 202) and tive and partly in section showing the closurethen into the lock pockets or depressions 200; cap removed from thebarrel; and and when this is accomplished and pressure on Fig. 7 is asection taken on the line l--l of Fig. the cap is relieved, the springpressed in inner cap IE will be tightly pressed against the adjacent endof the barrel and the lock lugs will be held seated in the pockets 200.In this way, by the simplest kind of a movement, the cap can be appliedand locked to the barrel so that it will not be accidentally displaced.

By reference to Fig. 6 it will be noted that the high point a: of theupper curve of channel 20b is circumferentially oflset toward pocket20c, beyond high point 3; of the lower curve of said channel. Whenspring-pressed inner cap it is engaged with the pen barrel and reactsagainst the same, the lugs I2 will be forced downward beyond high point1/ and into pocket Me. When pressure is relieved while pen barrel isstill at the highest possible point in channel 20b, the construction oflock pockets 20c prevents the pen locks from returning back throughchannel 20b, thereby assuring absolute protection against pen barrelbecoming separated from the cap. The relation of the points marked a:and 1 above noted is very important for the following reasons: Assumingthat the cap is held against rotation and that the pen is forced axiallyinto the cap, it is evident that the engagement of the lugs l2 with theupper curve of channel 20b will cause the pen to rotate in a clockwisedirection until the lugs l2 are moved in that direction beyond the pointy, thereby causing the lugs to move in the clockwise direction past thepoint 1 axially into the pocket 20c. Hence, when the tension on the penis removed, the lugs l2 will be automatically dropped into the pocketsMe. This rotary movement, which automatically locks the lugs in thepockets, is produced entirely by axial pressure between the cap and thepen and eliminates the necessity of a manual rotary operation in orderto locate the lugs in the pockets.

To release the cap it is only necessary to turn the same slightly so asto cam the lugs l2 out of the pockets 20c, thereupon the cap will befree for the passage of the lugs l2 out through the necks 20b andexpanded portions 20a.

With this structure the cap can be applied to the barrel simply byholding the cap between the fingers and pressing the thumb against thepressure plate or washer i3; and in this action the slight rotation ofthe barrel produced by the entrance of the lock lugs into the bayonetjoints will be freely permitted by rotation of the said pressure platel3.

In the drawing we have illustrated a cap formed with two flaring bayonetslots each extending circumferentially through 180, making a total flareof the two slots 360, so as to bring the flaring walls oi. the two slotsto sharp or wedge-like edges. This is important because it causes thelug or lugs on the barrel to be directed through the narrow channels andinto locked pockets. When the caps are pressed axially onto the barrel,the rotation of the cap will be due entirely to camming action. If, forexample, the cap should be formed with three flaring bayonet slots, theneach slot should flare through 120, making a total flare of 360. 1

What we claim is:

1. In a fountain pen, a barrel equipped at one end with a pen point andat the same end with a projecting lock lug, and a cap recessed to fltover the pen-equipped end of said barrel, said 1 recess being formedwith a bayonet slot that flares toward the open end of the cap, in onedirection, and in the other direction is contracted and formed with acircumferentially offset lock pocket to which the outer curve of said 2slot extends circumferentially in the direction of the pocket to a pointcircumterentially beyond the high point of the inner curve of saidcontracted neck, so that when said cap is pressed axially on to thebarrel, the lug of said barrel 2 will be moved circumferentially intosaid pocket.

2. The structure defined in claim 1 in further combination with ayielding pressure device mounted in said cap and adapted to be retractedby axial pressure and when released, to hold. 3

said lug in said pocket.

3. The structure defined in claim 1 in which said barrel at its oppositeend has a swiveled pressure plate adapted to remain stationary in thefinger pressing the same when said barrel 3 is rotated by the cammingaction oi. the slot of said cap. I

4. The structure deflned in claim 1 in-which said barrel at itsopposite'end has a swiveled pressure plate adapted to remain stationaryin 4 the flnger pressing the same when said barrel is rotated by thecamming action of the slot of said cap, said cap further having aretractable springpressed element with which the pen-equipped end a ofthe barrel is engageable when forced into said cap.

5. The structure defined in claim 1 in which said cap is provided with aplurality of said slots, the walls of which join at sharp-edged pointsso that under axial pressure the lug of said barrel will be caused tomove into one or the other of the said slots.

WALLACE E. LA MAY.

GEORGE w. CHANCE.

